Chronic traumatic encephalopathy (CTE) results from head injuries, not concussions. New research explains why 20% of athletes who exhibited the early stages of the progressive brain illness postmortem never had a diagnosed concussion.

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Chronic traumatic encephalopathy (CTE) results from head injuries, not concussions. New research explains why 20% of athletes who exhibited the early stages of the progressive brain illness postmortem never had a diagnosed concussion.